Conventionally, as a technique for automatically converting a source program, there is a technique in which development work is improved by automatically detecting differences between descriptions resulting from differences between compilers, and automatically correcting or listing the differences (see Patent Document 1, for example). According to this technique, a source program described in C language is parsed, a database and an intermediate file are created for each token, a target character string on the database is deleted or changed, information of the database and the intermediate file is generated in a C language file, and thus an object program is generated.    [Patent Document 1] JP 2002-41286A (p. 1, FIG. 1 etc.)